Study of Effects of Polymer Elasticity on Enhanced Oil Recovery by Core Flooding and Visualization Experiments

Polymer flooding is the simplest and one of the most widely used chemical Enhanced Oil Recovery (EOR) techniques. Viscoelasticity of polymers is known to contribute significantly towards improved displacement efficiency in polymer flood operations. But the contribution of elasticity of viscoelastic polymers in EOR still remains largely unexplored.;This study aims to delineate and investigate the individual effects of elasticity of partially hydrolyzed polyacrylamide (HPAM) polymer towards improved oil recovery. This was achieved by formulating polymers such that they have same average molecular weight (shear viscosity) but different molecular weight distribution (elasticity). Series of linear and radial core flooding experiments were conducted along with visual analysis.;Results from the experiments indicate that, polymer with higher elasticity gives higher recovery. Considering the molecular weight distribution together with average molecular weight seems to be a better approach for screening polymer for EOR. Elasticity of polymer solutions could well be used as a screening criterion for EOR applications.